Retaining wall cost dataset
This is the complete dataset behind the retaining wall calculator, at national wage rates. It is built on one correction to how these walls are usually quoted: the unit is a square foot of built face, not a linear foot, and the built face includes the buried course. Everything that makes a wall expensive scales with height while length simply repeats the same cross-section. Last reviewed 2026-08-24.
Height, and the two rates
| Visible | Built | Stone | Grid | Per lin ft | Per sq ft face | Cost |
|---|---|---|---|---|---|---|
| 2 ft | 2.7 ft | 6.2 t | — | $105 | $38.91 | $4,203 |
| 3 ft | 3.8 ft | 8.3 t | — | $144 | $37.88 | $5,758 |
| 4 ft | 4.9 ft | 10.4 t | 2 | $189 | $38.62 | $7,570 |
| 5 ft | 6 ft | 12.4 t | 2 | $284 | $47.28 | $11,346 ·eng |
| 6 ft | 7.1 ft | 14.5 t | 3 | $328 | $46.24 | $13,131 ·eng |
The two rate columns are the finding. Per linear foot the price runs from $105 to $328; per square foot of face it stays close to flat until the engineering threshold. ⚠️ Built height is visible height plus 10% plus a 0.5-foot base — so a wall showing three feet is 3.8 feet of wall. Geogrid appears above 3 feet on segmental block and repeats every couple of feet after that.
Length, which behaves the way people expect
| Length | Face area | Per linear ft | Cost |
|---|---|---|---|
| 20 ft | 76 sq ft | $144 | $2,874 |
| 40 ft | 152 sq ft | $144 | $5,758 |
| 60 ft | 228 sq ft | $144 | $8,632 |
| 100 ft | 380 sq ft | $144 | $14,396 |
| 200 ft | 760 sq ft | $144 | $28,797 |
Nearly linear, and gently cheaper per foot as it lengthens because the permit, the design and the setting up are paid once. That is the contrast worth holding onto: length repeats a cross-section, height changes it.
Material, soil and access
| Material | Life | Per year | Cost |
|---|---|---|---|
| Segmental concrete block | 50 | $115 | $5,758 |
| Poured reinforced concrete | 75 | $133 | $10,004 |
| Pressure-treated timber | 20 | $237 | $4,742 |
| Natural stone | 100 | $137 | $13,682 |
| Gabion baskets filled with rock | 40 | $170 | $6,809 |
| Condition | Cost |
|---|---|
| Sandy or gravelly | $5,590 |
| Loam or mixed | $5,758 |
| Clay | $6,039 |
| No machine access | $7,094 |
| 4 ft, nothing above it | $7,570 |
| 4 ft with a driveway above | $9,760 |
⚠️ The last two rows are the same wall. A surcharge above it — a driveway, a parking space, another wall — drops the height at which a stamped design is expected, so four feet with something on top is $2,190 more than four feet with nothing. The threshold itself is jurisdictional rather than federal: 4 feet in most places, three in some, and lower wherever there is load above. Your building department decides.
Line items
66% of the reference total comes from estimated rather than official figures. The reference wall is 40 feet long showing 3 feet — 3.8 feet built, 152 square feet of face — in segmental block on loam, with machine access: 8.3 tons of stone, 5.6 cubic yards excavated and 34.9 trade hours.
| Line item | Unit | Material | Equipment / hr | Trade | Data |
|---|---|---|---|---|---|
| Segmental concrete block — wall materialsquare feet of built face, when this material is chosen | sq ft of face | $11 – $26 | — | — | estimated±41% |
| Poured reinforced concrete — wall materialsquare feet of built face, when this material is chosen | sq ft of face | $24 – $52 | — | — | estimated±37% |
| Pressure-treated timber — wall materialsquare feet of built face, when this material is chosen | sq ft of face | $8.00 – $18 | — | — | estimated±38% |
| Natural stone — wall materialsquare feet of built face, when this material is chosen | sq ft of face | $32 – $78 | — | — | estimated±42% |
| Gabion baskets filled with rock — wall materialsquare feet of built face, when this material is chosen | sq ft of face | $14 – $32 | — | — | estimated±39% |
| Excavation behind and below the wallcubic yards, doubled without machine access | cu yd | — | $22 – $58 | — | estimated±45% |
| Compacted base and free-draining backfilltons of base plus drainage stone, scaled by soil | ton | $34 – $78 | — | — | estimated±39% |
| Perforated drain pipe, geotextile and outletswall length plus 15% for the run to daylight | linear ft | $3.40 – $8.50 | — | — | estimated±43% |
| Geogrid soil reinforcementlayers × length × embedment depth, above the threshold height | sq ft | $0.55 – $1.50 | — | — | estimated±46% |
| Setting the wallsquare feet of face × hours per sq ft for the material | hour | — | — | Brickmasons and Blockmasons | sourced |
| Placing base, drainage stone and backfilltons × 0.9 hours, ×1.8 without machine access | hour | — | — | Construction Laborers | sourced |
| Digging and barrowing by handcubic yards × 4 hours, only without machine access | hour | — | — | Construction Laborers | sourced |
| Machine operationcubic yards × 0.55 hours, with machine access | hour | — | — | Operating Engineers and Other Construction Equipment Operators | sourced |
| Engineered design and stamped drawings1 above the engineering threshold | each | $700 – $2,600 | — | — | estimated±58% |
| Permit and inspections1 when permitted, and always above the engineering threshold | each | $180 – $900 | — | — | estimated±67% |
| Steps built into the wallsteps built in | each | $140 – $420 | — | — | estimated±50% |
| Guardrail along the topwall length, when a guardrail is fitted | linear ft | $28 – $72 | — | — | estimated±44% |
The reasoning behind each figure
- Segmental concrete block — wall materialestimated, ±41%
- Interlocking dry-stacked block with a built-in batter, plus caps and the adhesive for them.
- ⚠️ Priced by square foot of built face, which includes the buried course. That is the number the trade works in and it is not the number a homeowner pictures: a wall you can see three feet of is roughly three and a half feet of wall.
- Poured reinforced concrete — wall materialestimated, ±37%
- Ready-mixed concrete, reinforcement and form hire for a reinforced stem wall on a footing.
- ⚠️ Priced by square foot of built face, which includes the buried course. That is the number the trade works in and it is not the number a homeowner pictures: a wall you can see three feet of is roughly three and a half feet of wall.
- Pressure-treated timber — wall materialestimated, ±38%
- Pressure-treated timbers, spikes and the deadmen that tie the wall back into the bank.
- ⚠️ Priced by square foot of built face, which includes the buried course. That is the number the trade works in and it is not the number a homeowner pictures: a wall you can see three feet of is roughly three and a half feet of wall.
- Natural stone — wall materialestimated, ±42%
- Quarried or fieldstone delivered. ⚠️ The material is a minority of the cost here; the fitting is the purchase.
- ⚠️ Priced by square foot of built face, which includes the buried course. That is the number the trade works in and it is not the number a homeowner pictures: a wall you can see three feet of is roughly three and a half feet of wall.
- Gabion baskets filled with rock — wall materialestimated, ±39%
- Galvanised baskets and the rock to fill them, which is a lot of rock and it has to come from somewhere near.
- ⚠️ Priced by square foot of built face, which includes the buried course. That is the number the trade works in and it is not the number a homeowner pictures: a wall you can see three feet of is roughly three and a half feet of wall.
- Excavation behind and below the wallestimated, ±45%
- Machine time and haulage for the trench under the wall and the space behind it for drainage stone.
- ⚠️ Doubled where there is no machine access, because the same soil then moves by shovel and wheelbarrow. The narrow side gate is the single most expensive feature a garden can have.
- Deep excavation on a slope is also the point where 29 CFR 1926 Subpart P starts to matter: a trench that a person works in has rules about sloping and shoring, and a bank above a wall is exactly where they apply.
- Compacted base and free-draining backfillestimated, ±39%
- Crushed stone for the levelling pad under the wall and the drainage zone behind it, delivered and placed.
- ⚠️ This is the line that decides whether the wall is still straight in ten years, and it is the first thing a cheap quote reduces because none of it is visible afterwards. A wall holds back soil; what pushes it over is water in that soil, and drainage stone is what stops the water becoming weight.
- Scaled by soil type: a clay site takes about a third more than a sandy one, because there is more water to move and the soil itself will not pass it.
- Perforated drain pipe, geotextile and outletsestimated, ±43%
- Perforated pipe at the base of the drainage stone, wrapped in geotextile so it does not silt up, and taken to daylight at one or both ends.
- ⚠️ The outlet is the part that gets forgotten. A drain that runs to a dead end is a bathtub: it fills the drainage zone with the water it was installed to remove. Ask where the pipe comes out, and go and look at the end of it.
- Geogrid soil reinforcementestimated, ±46%
- Layers of structural mesh laid between courses and extending back into the retained soil, so the wall and the soil behave as one mass.
- ⚠️ On a segmental wall above about three feet this is the engineering. The blocks are a facing; what holds the bank back is the grid buried behind them, and it has to reach far enough into the soil to matter. Priced as roughly 70% of the wall height in depth, on a layer every third course.
- Its absence is invisible on the day and obvious in five years, which is why a quote that never mentions it on a tall wall is worth questioning before it is worth comparing.
- Setting the wall
- Between 0.14 and 0.42 hours per square foot of face depending on the material — timber at the bottom, fitted natural stone at the top, a three-fold spread.
- The first course is most of the skill and a disproportionate share of the time: it is set on compacted stone, levelled in both directions, and every error in it is repeated all the way up.
- Placing base, drainage stone and backfill
- About 0.9 hours per ton of stone placed and compacted in layers, plus laying the grid and the pipe.
- Compacting in layers is not optional and it is not quick. Stone tipped in and driven over once behaves like loose fill, and loose fill behind a wall settles — which pulls the top of the wall backwards and then forwards.
- Digging and barrowing by hand
- About 4 hours per cubic yard where no machine can reach the wall: dug with a shovel, moved with a barrow, and every yard of it handled twice.
- ⚠️ This is what a narrow side gate really costs — about a fifth more on a small wall, and a growing share as the wall gets taller and the excavation with it. A mini excavator moves a cubic yard in minutes; two labourers with barrows move it in an afternoon. Before asking for quotes, measure the narrowest point on the route and say what it is.
- Machine operation
- An operator for the excavation and for moving material about the site. Only where a machine can get in.
- Where it cannot, the hours do not disappear — they move to the labourer line and roughly double, which is what the access question really costs.
- Engineered design and stamped drawingsestimated, ±58%
- ⚠️ Priced automatically above 4 feet of retained height, and above 3 feet where there is a surcharge or a slope above the wall.
- A site visit, soil assumptions, calculations and a sealed drawing set that the building department will accept. The engineer also specifies the grid layout, which is the part that decides whether the wall works.
- The threshold itself is jurisdictional rather than federal and it varies — three feet in some places, four in most, lower wherever something is parked or driven above the wall. Your building department decides; this line exists so the cost is in the estimate rather than in a surprise.
- Permit and inspectionsestimated, ±67%
- Application, plan review and the inspections that go with it — normally one before the base is covered and one at completion.
- A retaining wall changes where water goes on a plot, which is why some jurisdictions review them even when they are short.
- Steps built into the wallestimated, ±50%
- Per step, including the extra base, the cut blocks and the labour of setting them into the run.
- Steps interrupt the courses, so each one is fiddly out of proportion to its size. They are also the part people use every day, which is an argument for getting them right rather than cheap.
- Guardrail along the topestimated, ±44%
- Posts set behind the wall rather than into the block, and rail between them.
- ⚠️ Many jurisdictions require a barrier where there is a drop above a certain height and a walking surface beside it. It is worth asking at the same time as the permit, because posts are far cheaper to plan for than to retrofit into a finished wall.
Not included in this dataset
- Fixing why the ground is moving
- A wall built to hold a bank that is actively sliding is a wall in the way of a landslide. Where there is real slope instability the question is geotechnical and it comes before any price for block.
- Removing the old wall
- Taking out a failed timber or block wall, and dealing with whatever comes down with it, is its own job — and it is unpredictable, because nobody knows what is behind it until it is out.
- Landscaping above and below
- Levelling, topsoil, planting and turf are what makes the finished thing look like anything. None of it is priced here.
- Utilities in the way
- Digging a trench along a boundary finds gas, water, irrigation and cable often enough to be worth planning for. Call 811 before anybody breaks ground; locating is free and hitting a line is not.
- Tiered walls
- Two shorter walls stepped back look like a way round a height limit and are not: each wall surcharges the one below unless the setback is large enough, and the pair is normally engineered as a single taller structure.
- What the neighbours think
- Retaining walls sit on boundaries, change where water goes, and outlive the people who build them. A conversation and, where the boundary is unclear, a survey are worth more than any line on this page.
Use the calculator, price the patio above or below it, or read the full method.